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Jan 29
Car Diagnostics Belfast

Frequently Asked Questions - Northern Ireland

Call Us on 07851990331 - Car Diagnostics Belfast Northern Ireland

What is OBD, and what are its benefits?

OBD stands for "on-board diagnostics," a computer-based system built into all model year (MY) 1996 and newer light-duty cars and trucks. OBD monitors the performance of some of the engines' major components, including individual emission controls. The system provides owners with an early warning of malfunctions by way of a dashboard "Check Engine" light (also known as a Malfunction Indicator Light or MIL, for short). By giving vehicle owners this early warning, OBD protects not only the environment but also consumers, identifying minor problems before they become major repair bills.

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How do I know the OBD system is working correctly?

When you turn on the ignition, the "Service Engine Soon" or "Check Engine" light should flash briefly, indicating that the OBD system is ready to scan your vehicle for any malfunctions. After this brief flash, the light should stay off while you drive as long as no problems are detected. If so, you'll be glad to know that your vehicle is equipped with an early warning system that could save you time, money, and fuel in addition to helping protect the environment!

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What does it mean if the light turns on while I'm driving?

If the light comes on and stays on, the OBD system has detected a problem. Your vehicle might have a condition that wastes fuel, shortens engine life, or causes excessive air pollution. If left unaddressed, these conditions could also damage your vehicle and lead to increasingly expensive repairs. For example, OBD can identify a loose or missing gas cap (which wastes fuel and contributes to smog) or engine misfire (which can lead to severe or permanent engine damage).

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What should I do if the light stays on?

There is no cause for panic. The vehicle is just telling you to seek attention soon. When you reach your destination, make sure the gas cap is not loose or missing. Always turn off your engine when refueling. If the light does not go out after a few short trips following gas cap replacement or tightening, have your vehicle serviced by a qualified repair technician soon! Delaying assistance could lead to more expensive damage.

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What does it mean if the light is blinking?

If the light is blinking, a severe engine problem such as a catalyst-damaging misfire is occurring and should be addressed as soon as possible. You can still drive safely, but should minimize your time on the road. Try not to drive the vehicle at high speed or with excess weight (such as towing or carrying heavy equipment).

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What will my Clear Vehicle Diagnostics technician do when I take my vehicle to him?

We have an OBD scan tool (a small, hand-held scanning device) to diagnose the cause of your vehicle's problem. Our technicians will have the proper tools and will know best how to diagnose your vehicle.

The technician will connect the scan tool to your vehicle's computer (usually through a connector under the dashboard) and download information that can pinpoint the problem. The technician can then repair the vehicle based on manufacturer recommendations. OBD actually helps repair technicians do their job more quickly and reliably, helping you avoid unnecessary repairs and trips back to the shop.

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Are repair costs going to increase?

Thus far, no increase has been seen. Real world experience from operating programs has shown that the average cost for an OBD-triggered repair is comparable to that associated with repairs triggered as a result of more traditional tailpipe testing of OBD-equipped vehicles. Regardless of the test used to identify a failure in the I/M lane, it is standard operating procedure for a repair technician to consult a vehicle's OBD system before attempting a repair. In fact, the repair community has been using the kind of information provided by OBD systems to diagnose and repair vehicles for more than twenty years. The fact that these systems and the information they provide has been standardized since MY1996 makes using this information easier while leading to more accurate and quicker diagnoses and more cost-effective repairs than possible with earlier OBD systems.

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Can the OBD system be repaired, deactivated, or modified?

The rule of thumb when it comes to emissions-related vehicle repair is that any modification that changes the vehicle from a certified configuration to a non-certified configuration is considered tampering: this applies to both vehicle owners and repair facilities and is, therefore, a Federal offense. Replacing a catalyst with a straight pipe is one traditional example of tampering. Likewise, overriding the OBD system through the use of high-tech defeat devices or non-certified computer chips, for example, would also be considered tampering. The OBD system may, however, be repaired back to its original certified configuration with certified "performance chips" or appropriate aftermarket parts.

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What should I do if the light goes out before I take the vehicle to the shop?

Usually, nothing. If the problem that caused the light to come on is addressed, the OBD computer will turn the light off. This is not an indication of a faulty OBD system. In fact, the system is doing its job by verifying that a problem temporarily existed but has since been corrected; perhaps a loose gas cap was tightened or a fouled spark plug was cleared. Your vehicle needs no special attention unless the light comes on again.

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